Flavor biotransformation of “Uiseong” garlic during the fermentation process by lactic acid bacteria

Abstract

This study investigates the biotransformation of Uiseong garlic, a South Korean variety renowned for its distinct sulfur compounds, by lactic acid bacteria (LAB) during kimchi fermentation. Using GC–MS, 26 volatile compounds, including 3-vinyl-1,2-dithiocyclohex-4-ene and 3-vinyl-1,2-dithiocyclohex-5-ene, were identified in garlic extracts. Four LAB strains active in early-stage kimchi fermentation degraded primary sulfur compounds and produced unique metabolites, such as pyrazine and allyl methyl disulfide. These biotransformed compounds reduced garlic’s pungency while enhancing savory and umami flavors, creating a balanced and complex sensory profile. Strain-specific differences and fermentation conditions, especially temperature, significantly influenced flavor development. The findings underscore Uiseong garlic’s pivotal role in flavor modulation and its potential for consistent quality in commercial kimchi production. This research can be applied to flavor transformation mechanisms and supports precision fermentation strategies to optimize sensory profiles and meet consumer preferences.